During a Dec. 20 news conference, Sun Prairie Police Chief Chief Patrick Anhalt said the explosion followed a natural gas line being hit by a crew from Michigan-based VC Tech after the intersection of Main and Bristol streets was improperly marked.

But officials went on to say they have found no probable cause to believe a crime was committed in connection with the explosion.

OSHA investigators say Bear Communications failed to contact Diggers Hotline prior to digging to install a fiber optic line. According to OSHA, VC Tech also did not contact the one-call center prior to excavation.

“I think it is very important that a federal agency identified that,” Diggers Hotline spokesperson Chad Krueger tells 27 News. “I know it’s part of OSHA’s regulations. I know there’s a specific example in their regulations about people knowing where underground lines are.”

According to the citations: “Utility companies or owners were not contacted within established or customary local response times, advised of the proposed work and asked to establish the location of the utility underground installations prior to the start of an excavation.

“I’m sure everyone is more aware, more careful, double checks what they’re doing now, where they might not have in the past, just felt they had the information and went with it,” Esser says. “I bet now they’re more cautious.

Sun Prairie Police reports show a previous contractor contacted Diggers Hotline about planned excavation in the section of Sun Prairie’s downtown, but left the project. The utility-locating company did not finish marking the site when the first contractor quit, and Bear and VC Tech employees relied on incomplete information when they assumed the job.

The companies have the option to contest the amount of the citation if they request a conference within 15 days. Representatives of the two firms have to comment.

Hebl says he is working with Wisconsin utilities and other stakeholders to craft proposed legislation to address instances of vital information in excavation work falling through the cracks, as happened in Sun Prairie.